Plunger-elevator.



J. S. HOYT.

PLUNGER ELEVATOR.

APPLICATION IILIID MAILIS), 1912. RENEWED MAY 2.1914

1, l 1 8,347. Patented Nov. 24, 1914.

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JOHN SHERMAN I-IOYT, OF DARIEN, CONNECTICUT.

PLUNGER-ELEVATOR.

Specification of Letters Patent.

Patented Nov. 24,191. 1.

Application filed MarchlS, 1912,Seria1 No. 684,892. Renewed May 2, 1914.Serial No. 835,998.

To all whom it may concern:

Be it known that I, JOHN SHERMAN I-IoY'r, a citizen of the UnitedStates, residing at Darien, in the county of Fairfield and State ofConnecticut, have invented certain new and useful Improvements inPlunger-Elevators, of which the following is a full, clear, and exactspecification.

This invention relates to plunger elevators, and has particularreference to means for automatically relieving the plunger of liftingforce when it exceeds the normal upper limit of travel, so as to openthe cylinder to exhaust and positively stop the car before the plungercan jump out of the cylinder. In the form of the invention hereinillustrated, this result is accomplished by means of a valve which isnormally closed during the ordinary operation of the elevator, butwhich,upon an abnormal rise of the plunger, becomes mechanicallyconnected therewith and positively actuated thereby to open a relief orby-pass from the cylinder to the exhaust, entirely independently of theusual controlling valve and automatic limitation stop valve. Means isprovided for automatically closing this valve upon descent of theplunger below the danger point.

In the accompanying drawings, Figure 1 is an elevation of a portion ofaplunger elevator system embodying the invention; Fig. 2 is a crosssection showing the plunger and one form of operating means; Fig. 3shows a modification, wherein the valve controlling the relief is withinthe cylinder; and Fig. 1 is a cross section of Fig. 3 seen from below.

1 represents a plunger cylinder having a cylinder head and stuffing-box9. of suitable construction, and connected adjacent the end with ato-and-fro pipe 3, which will be controlled by automatic valves and amain valve in any suitable or desired manner, not shown herein.

4 represents a plunger carrying at its upper end a car 5 of any desiredconstruction not necessarily to be shown herein. At or adjacent thelower end of the plunger a guiding means is provided for preventing theend of the plunger from scraping and wearing on the interior of thecylinder, and also tending to lessen vibration. As herein shown, thisguiding means consists of rollers 6 carried by a plunger bottom 7, theplun- :ger bottom being also provided with pro] ecting lugs 8,011eofwhich lugs is adapted to engage and lift the relief valve operating rod9 when the plunger end approaches within a predetermined distance ofthe, top of the cylinder. When one of the lugs 8 strikes the rod 9, it,through a lever ll) and link 11, opens the normally closed valve 12 todis charge water from the cylinder through the pipe 13. The particularlocation of the valve 12 and pipe 13 may be varied as desired, butshould preferably be placed as close to the cylinder and in as directcommunication therewith as possible, so that when operated it willpositively relieve the plunger of lifting force and stop the car beforethe plunger can jump out of the cylinder or violently strike thecylinder head 2. As shown in Fig. 1,.the rod 9 slides through a smallpacking and the lever 10 is pivoted to a lug14= carried by the cylinderhead 2.

15 is a spring which normally holds the valve 12 closed, so that therewill be no lcak age or operation of the valve 12 during the normaloperation of the elevator.

It will be seen that this invention, is not intended to operate everytime the elevator reaches the upper landing, but is an emer gcncy devicewhich will operate in case the plunger rises abnormally high, such as incase of failure of the operator to stop the car or of the automaticvalve to operate. The guiding means for the end of the plunger may bevaried in. details of construction or be made resilient withoutaffecting this invention.

In Figs. 3 and 4:, the relief passage 13 extends laterally from thecylinder, and is normally kept closed by a cylindrical sleeve 18 havingports 19, being pressed down to close the ports 19 by a spring 20. Thesleeve is provided with lugs 21 which are engaged by the lugs orprojections 8 on the plunger and thereby the sleeve 18 lifted and theports opened, and thereby stops the car in the manner before described.

The invention is especially useful in conjunction with plunger elevatorsof high rise and high speed, wherein, on account of the length and greatweight of the plunger, it may acquire such momentum as to overrun thenormal upper limit in case the controlling valves should not operate tocut off the supply pressure. \Vith this invention in case the supplypressure should not be cut oil, upon the opening of the valve, it wouldbe simply discharged outside the cylinder and the plunger would stopbecause of its own weight.

Various changes and modifications in the details of construction and thearrangement of the parts may be made without departing from the scope ofthe invention.

Having thus described my invention, I declare that what I claim as newand desire to secure by Letters Patent is:

l. The combination with, a cylinder and a plunger, of means comprising anormally closed valve for opening said cylinder to exhaust, and meanscarried by the plunger for operating said valve at a predetermined pointor" the travel.

2. The combination with a cylinder and a plunger, of means comprising anormally closed valve for opening said cylinder to exhaust, and 1 canscarried by the plunger for operating said valve at a predetermined pointof the upward travel.

3. The combination with a cylinder and a plunger, of means comprising anormally closed valve located adjacent the cylinder head for openingsaid cylinder to exhaust, and means carried by the plunger for operatingsaid valve at a predetermined point of the travel.

4. The combination with a cylinder and a direct acting plunger elevator,of a normally closed valve for openingthe cylinder to exhaust, and meanswithin the cylinder and operated by the plunger at a predetermined pointfor opening said valve.

The combination with a cylinder and a direct acting plunger elevator, ofa normally closed valve for opening the cylinder to exhaust, meanswithin the cylinder and operated by the plunger at a predetermined pointfor opening said valve, and means for closing said valve upon descent ofthe plunger.

6. The combination with a cylinder and a plunger, of a normally closedvalve connecting the cylinder with an exhaust, and

means for opening said valve when the plunger reaches an abnormalposition.

7. The combination with a cylinder and a plunger, of a normally closedvalve connecting the cylinder with an exhaust, and means for openingsaid valve when the plunger reaches an abnormal upward position.

' 8. The combination with a cylinder and a plunger, of a normally closedvalve connecting the cylinder with an exhaust, means for opening saidvalve when the plunger reaches an abnormal upward position, and meansfor closing said valve upon descent of the plunger from abnormalposition.

9. The combination with a cylinder and a plunger, of guiding means.adjacent the end of the plunger adapted to engage the stuliing box, anormally closed valve for opening said cylinder to exhaust, and meansfor opening said valve before said guiding means engages the stuflingbox.

10. The combination with a cylinder and a plunger, of guiding meansadjacent the end of the plunger adapted to engage the stufling box, anormally closed valve for opening said cylinder to exhaust, and meansoperated by said plunger for opening said valve before said guidingmeans engages the stufling box.

11. The combination with a cylinder and a plunger, of guiding meansadjacent the end of the plunger adapted to engage the stuiling box, anormally closed valve for opening said cylinder to exhaust, and meansoperated by said plunger guiding means for opening said valve beforesaid guiding means engages the stuffing box. 7

12. The combination with a cylinderand a plunger, of a valve for openingthe cylinder to the exterior, and means operated by the plunger forpositively opening said valve.

In testimony whereof I aflix my signature, in presence of two witnesses.

JOHN SHERMAN HOYT.

lVitnesses J. S. Voosrnn, G. N. KERR.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington. D. C.

